3-Phase Electrical Installation Manchester
Single-phase electricity supplies are limited to approximately 100A (24kW), which quickly becomes a bottleneck for businesses and larger properties looking to install commercial solar arrays or large battery storage systems. A 3-phase supply delivers three times the capacity, enabling you to run high-power equipment, balance loads across phases and install renewable energy systems that would be impossible on a single-phase connection.
Manchester Renewables provides complete 3-phase electrical installation and upgrade services across Greater Manchester. From applying to your Distribution Network Operator (DNO) for a 3-phase supply upgrade through to designing the 3-phase distribution board, wiring all circuits and commissioning the system, our NIC/EIC Approved electricians handle every stage. We specialise in 3-phase work for commercial solar PV installations and large battery storage systems.
What Is Included?
DNO Application & Supply Upgrade
We manage the entire application process with your Distribution Network Operator (Electricity North West in Manchester) for upgrading from single-phase to 3-phase supply, or increasing your existing 3-phase capacity.
3-Phase Distribution Board Design
Custom distribution board design with balanced load allocation across all three phases. We use commercial-grade boards from Hager and Schneider with MCCB protection and metering provisions.
Commercial Solar & Battery Wiring
3-phase inverter connection and commissioning for commercial solar PV systems from 10kW to 200kW+. Includes 3-phase battery storage integration and export limitation where required by the DNO.
Testing, Certification & Commissioning
Full 3-phase testing including phase rotation, load balancing verification and fault loop impedance on all circuits. Electrical Installation Certificate and commissioning report issued for every installation.
BS 7671 18th Edition — 3-Phase Installations & G99 Grid Connection: Mandatory for systems above 16A per phase
All 3-phase electrical installations must comply with BS 7671 18th Edition Wiring Regulations, with particular attention to load balancing, neutral sizing and protective device coordination across phases. Solar PV and battery systems connected via 3-phase supplies above 16A per phase require a G99 application to the DNO, which involves a detailed technical assessment and may take 8-12 weeks for approval. Our electricians are experienced in both BS 7671 3-phase design and the G99 application process.
Why It Matters
- A single-phase supply cannot support a commercial solar system above approximately 3.68kW without export limitation
- Large commercial solar or battery systems on single-phase cause phase imbalance that can trip your supply and damage equipment
- 3-phase systems deliver power more efficiently with lower cable losses over long distances
- Many commercial landlords and property developers require 3-phase infrastructure for planning compliance
Cost Guidance
The cost of a 3-phase electrical installation varies significantly depending on the scope of work. A DNO supply upgrade from single-phase to 3-phase typically costs between £1,500 and £5,000 depending on the distance from the nearest 3-phase transformer and the work required by Electricity North West. Internal 3-phase distribution board installation and wiring ranges from £2,000 to £8,000+ depending on the number of circuits, cable runs and equipment. For a complete 3-phase commercial solar installation including inverter wiring and grid connection, expect to pay £3,000 to £12,000 for the electrical element. We provide detailed, itemised quotations after a site survey.